lsst.sphgeom  19.0.0-4-g8557e14+3
Angle.h
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22 
23 #ifndef LSST_SPHGEOM_ANGLE_H_
24 #define LSST_SPHGEOM_ANGLE_H_
25 
28 
29 #include <cmath>
30 #include <algorithm>
31 #include <iosfwd>
32 #include <limits>
33 
34 #include "constants.h"
35 
36 
37 namespace lsst {
38 namespace sphgeom {
39 
43 class Angle {
44 public:
45  static Angle nan() {
46  return Angle(std::numeric_limits<double>::quiet_NaN());
47  }
48 
49  static Angle fromDegrees(double a) { return Angle(a * RAD_PER_DEG); }
50 
51  static Angle fromRadians(double a) { return Angle(a); }
52 
54  Angle() : _rad(0.0) {}
55 
57  explicit Angle(double a) : _rad(a) {}
58 
59  // Comparison operators
60  bool operator==(Angle const & a) const { return _rad == a._rad; }
61  bool operator!=(Angle const & a) const { return _rad != a._rad; }
62  bool operator<(Angle const & a) const { return _rad < a._rad; }
63  bool operator>(Angle const & a) const { return _rad > a._rad; }
64  bool operator<=(Angle const & a) const { return _rad <= a._rad; }
65  bool operator>=(Angle const & a) const { return _rad >= a._rad; }
66 
67  // Arithmetic operators
68  Angle operator-() const { return Angle(-_rad); }
69  Angle operator+(Angle const & a) const { return Angle(_rad + a._rad); }
70  Angle operator-(Angle const & a) const { return Angle(_rad - a._rad); }
71  Angle operator*(double a) const { return Angle(_rad * a); }
72  Angle operator/(double a) const { return Angle(_rad / a); }
73  double operator/(Angle const & a) const { return _rad / a._rad; }
74 
75  // In-place arithmetic operators
76  Angle & operator+=(Angle const & a) { *this = *this + a; return *this; }
77  Angle & operator-=(Angle const & a) { *this = *this - a; return *this; }
78  Angle & operator*=(double a) { *this = *this * a; return *this; }
79  Angle & operator/=(double a) { *this = *this / a; return *this; }
80 
82  double asDegrees() const { return _rad * DEG_PER_RAD; }
83 
85  double asRadians() const { return _rad; }
86 
88  bool isNormalized() const { return _rad >= 0.0 && _rad <= 2.0 * PI; }
89 
91  bool isNan() const { return std::isnan(_rad); }
92 
93 private:
94  double _rad;
95 };
96 
97 
98 inline Angle operator*(double a, Angle const & b) { return b * a; }
99 
100 std::ostream & operator<<(std::ostream &, Angle const &);
101 
102 inline double sin(Angle const & a) { return std::sin(a.asRadians()); }
103 inline double cos(Angle const & a) { return std::cos(a.asRadians()); }
104 inline double tan(Angle const & a) { return std::tan(a.asRadians()); }
105 
106 inline Angle abs(Angle const & a) { return Angle(std::fabs(a.asRadians())); }
107 
108 }} // namespace lsst::sphgeom
109 
110 #endif // LSST_SPHGEOM_ANGLE_H_
lsst::sphgeom::Angle::asDegrees
double asDegrees() const
asDegrees returns the value of this angle in units of degrees.
Definition: Angle.h:82
lsst::sphgeom::Angle::asRadians
double asRadians() const
asRadians returns the value of this angle in units of radians.
Definition: Angle.h:85
lsst::sphgeom::Angle::isNormalized
bool isNormalized() const
isNormalized returns true if this angle lies in the range [0, 2π).
Definition: Angle.h:88
lsst::sphgeom::Angle
Definition: Angle.h:43
lsst::sphgeom::Angle::Angle
Angle(double a)
This constructor creates an Angle with the given value in radians.
Definition: Angle.h:57
lsst::sphgeom::Angle::isNan
bool isNan() const
isNan returns true if the angle value is NaN.
Definition: Angle.h:91
lsst::sphgeom::Angle::Angle
Angle()
This constructor creates an Angle with a value of zero.
Definition: Angle.h:54
constants.h
This file contains common constants.